OBJECTIVES: 1. The biosynthesis of rhodopsin is being studied in normal rats, and rats suffering from hereditary retinal degeneration (RCS rats). 2. The biochemistry of the pigment epithelium in normal and RCS rats is under investigation, using radioactive precursors to study protein synthesis and turnover. 3. A study is underway concerning the chemistry and molecular architecture of the plasma membrane of the pigment epithelium and the rod outer segment in normal and RCS rats.